MAR 1 2 2001 KFC 22 .W750 :89 no. 120 OF WATER CONDITIONS 1' 2001 season in a water prospects in the season have been February precipitation. Seasonal accumulations of rain and have improved significantly from one month ago. south caught up to normal but northern and the northeastern part of be adequate this year. been raised to about 70 percent overall, with in the Shasta - Trinity area and lowest in the Northern Lahontan Water year forecasts, assuming normal weather henceforth, are about 60 percent of average statewide compared to 95 percent actual runoff last year. Snowpack water content has improved to 85 percent of average for this date, compared to 120 percent last year. The pack is about 70 percent of the April1 average, which is the date of maximum accumulation. As noted last month, the bigger percentages are in the lower portion of the snow zone; amounts near the crest of the Sierra are considerably lighter. Precipitation during February was about 120 percent of average for the month and boosted seasonal precipitation to 75 percent of average compared to 60 percent one month ago and 105 percent a year ago. Monthly precipitation was heaviest in the southern part of the State and in the coastal regions from San Francisco Bay southward. Runoff so far this season continues to lag and is about 40 percent of average compared to 95 percent one year ago. February runoff was about 50 percent of average. Estimated runoff of the eight major rivers of the Sacramento and San Joaquin River regions was 1.5 acre-feet in February. Reservoir storage increased at approximately the normal pace during the month and is near average for this date statewide. Last year storage was higher at 120 percent of average. Lake Oroville gained about 0.1 million acre-feet during February but remains much below average. SUMMARY OF WATER CONDITIONS IN PERCENT OF AVERAGE HYDROLOGIC REGION PRECIPITATION MARCH 1 SNOW MARCH 1 RUNOFF OCTOBER 1 TO WATER CONTENT RESERVOIR OCTOBER 1 TO DATE STORAGE DATE 55 90 95 25 80 60 90 105 40 100 130 50 100 95 25 SACRAMENTO RIVER 70 85 95 50 70 60 ···································································· SAN JOAQUIN RIVER 85 85 115 35 70 60 ··········································································· TULARE LAKE 80 85 90 40 65 60 NORTH LAHONTAN 45 65 120 45 55 50 SOUTH LAHONTAN 75 80 75 COLORADO RIVER­ DESERT 165 STATEWIDE 75 85 100 40 70 60 1 SEASONAL PRECIPITATION IN PERCENT OF AVERAGE TO DATE October 1, 2000 through February 28, 2001 Statewide = 75°/o f Hydrologic Regions NC - North Coast SF - San Francisco Bay CR CC - Central Coast SC - South Coast 165o/~ SR - Sacramento River SJ - San Joaquin TL - Tulare Lake NL - North Lahontan SL - South Lahontan CR - Colorado River-Desert WATER YEAR IS OCTOBER 1 THROUGH SEPTEMBER 30 2 FORECAST OF APRIL - JULV UNIMPAIRED SNOWMELT RUNOFF March 1, 2001 Legend 1 OOo/o Runoff forecast in percent of nonnal UPPER SACRAMENTO 83°/o TRINITY 83o/o N FEATHER 60°/o YUBA 68°/o TRUCKEE 4 7o/o AMERICAN 67°/o TAHOE 43°/o l CARSON 57°/o COSUMNES 66o/o WALKER 60°/o MOKELUMNE 70°/o TUOLUMNE 71 °/o - OWENS. 79°/o KINGS 66°/o- KE RN 54°/o • FORECAST BY DEPARTMENT OF WATER AND POWER, CITY OF LOS ANGELES 3 APRIL-JULY UNIMPAIRED RUNOFF SACRAMENTO RIVER 726 Sacramento River above Bend Feather River Feather River at Lake Almanor near 21 63% North Fork at (3) 243 620 60% Middle Fork near Clio (4) 86 518 4 45 52% South Fork at Ponderosa Dam 1 267 13 60 55% Total Inflow to Oroville Reservoir 392 1 60% 750 - Yuba River North Yuba below Bar (3) 286 647 51 190 66% Inflow to Jackson Mdws and Bowman Reservoirs (3) 112 236 25 75 67% South Yuba at Langs (3) 233 481 57 150 64% Yuba River at Smartville 1 200 700 68% 440 - American River North Fork at North Fork Dam (3) 262 716 43 170 65% Middle Fork near Auburn (3) 522 1,406 100 340 65% Silver Creek Below Camino Diversion Dam (3) 173 386 37 110 64% Total Inflow to Folsom Reservoir 1 3,074 229 840 67% 540 - SAN JOAQUIN RIVER Cosumnes River at Michigan Bar 128 363 8 85 66% 50 - 185 Mokelumne River North Fork near West Point (5) 437 829 104 290 66% Total Inflow to Pardee Reservoir 459 1 02 320 70% 220 - 540 Stanislaus River Middle Fork below Beardsley Dam (3) 334 702 64 220 66% North Fork Inflow to McKays Point Dam (3) 224 503 34 150 67% Total Inflow to New Melones Reservoir 699 1 116 480 69% 280 - 810 Tuolumne River Cherry Creek & Eleanor Creek near Hetch (3) 322 727 97 230 71% Tuolumme River near Hetch Hetchy (3) 606 1,392 153 440 73% Total Inflow to Don Pedro Reservoir ,184 301 840 71% 550 - Merced River Merced River at Pohono (3) 362 888 80 270 75% Total Inflow to Lake McClure 611 1 123 440 72% 320 750 San Joaquin River San Joaquin River at Mammoth Pool (6) 235 680 67% Big Creek below Huntington Lake (6) 95 264 11 60 63% South Fork near Florence Lake (6) 202 511 58 130 64% Total Inflow to Millerton Lake 262 830 68% 550 - 1,380 Kings River North Fork Kings River near Cliff (3) 565 50 150 63% Total Inflow to Pine Flat Reservoir 114 273 780 66% 510 - 1,290 Kaweah River at Terminus Reservoir 4 61 190 69% 130 - 330 Tule River at Success Reservoir 259 2 34 58% 20 - 78 Kern River Kern River near Kernville (3) 83 200 54% Total Inflow to Isabella Reservoir 84 240 54% 170 490 (1) See inside back cover for definition (4) 44 year average based on years 1936-79 (2) All 50 year averages are based on years 1946-1995 unless otherwise noted (5) 36 year average based on years 1936-72 (3) 50 year average based on years 1941-90 (6) 45 year average based on years 1936-81 4 280 1 '' 160 ~ 8,170 780 366 7 666 219 637 24 291 562 32 994 495 220 70 2,400 53% 564 102 81 292 30 379 565 98 4,926 369 165 95 260 300 280 95 25 30 1 53% 890 - 2,050 616 1,234 66 1,070 144 318 705 59 349 180 2,420 378 20 9 21 54 50 25 7 3 180 48% 120 - 345 626 197 736 129 35 55 120 150 45 5 5 430 58% 300 - 690 929 88 1 '131 155 65 35 90 170 200 90 20 0 680 60% 450 - 1,090 461 1,147 123 770 1 258 383 90 60 145 250 25 62% 820 - 461 1,020 92 952 150 40 30 80 130 190 100 20 600 63% 460 - 980 1 308 112 298 14 248 653 71 362 80 40 220 60 40 63% 780 - 284 607 58 383 70 75 180 50 30 990 60% 690 - 1,590 431 1,402 92 25 27 55 80 45 10 260 60% 190 - 440 135 615 16 12 7 15 16 13 4 68 50% 45 - 135 558 163 694 175 50 20 65 25 25 53% 280 690 runoff in prior months based on measured flows 5 MARCH 1, 2001 FORECASTS APRiL-JULY UNIMPAIRED RUNOFF Unimpaired Runoff in 1,000 Acre-Feet (1) HYDROLOGIC REGION HISTORICAL FORECAST and Watershed 50 Yr I Max Min Apr-Jul 1 Pet Avg I of of Forecasts I of (2) I Record Record Avg NORTH COAST Trinity River Total Inflow to Lewiston Lake 642 1,593 80 530 83% Scott River Near Fort Jones 200 n/a n/a 130 65% Klamath River Total inflow to Upper Klamath Lake (3) 509 758 280 255 50% NORTH LAHONTAN Truckee River Lake Tahoe to Farad accretions 264 713 58 125 47% Lake Tahoe Rise (assuming gates closed, in feet) 1.4 3.6 0.2 0.6 43% Carson River West Fork at Woodfords 54 135 12 30 56% East Fork near Gardnerville 183 407 43 105 57% Walker River West Fork near Coleville 143 330 35 90 63% East Fork near Bridgeport 61 209 7 30 49% SOUTH LAHONTAN Owens River Total tributary flow to Owens River (4) 226 579 96 179 79% (1) See inside back cover for definition (2) All 50 year averages are based on years 1946-1995 unless otherwise noted (3) Forecast by U.S. Natural Resources Conservation Service and National Weather Service California-Nevada River Forecast Center, April through September forecast, 30 year average based on years 1961-1990. (4) Forecast by Department of Water and Power, City of Los Angeles 6 Snowpack Accumulation NORTH COAST REGION Water Content in % of April 1 Average SNOWPACK- First of the month measurements 250 ----------------------------------------------------------------------· made at 10 snow courses indicate an area wide snow 225 Maximum water equivalent of 22.4 inches. This is 90 percent of 200 ----------------------------------:_::--:_::-·:.::;·--:.::;--:.::;--=-·=--~-"'-"--=-·:..:.··::.:··:.:_···:.:_:··· the March 1 average and 75 percent of the seasonal 175 (April 1) average. Last year at this time the pack was 150 holding 4 i. 0 inches of water. 125 ---- ----------------------------------------------------------------· 100 75 50 25~~~~==---=---=--=---~--=---~--~---=--~-~~~ oJ---~------~--------.-------.---- Jan 1 Feb 1 Mar 1 Apr 1 May 1 Precipitation October 1 to date in %of Average 250 ------------------------------------------------------------------------ PRECIPITATION- Seasonal precipitation 225 -----------.------------------------------------------------------------ (October 1 through the end of last month) on this 200 -------------------------------------------------------------------------. area was 55 percent of normal. Precipitation last 175 -------------------------- ---- -------------------------------------------. month was about 80 percent of the monthly average. 150 -------------------------------------------------- -- ---------------------. Seasonal precipitation at this time last year stood at 125 -- -- ---------------------------------------------------------------------- 105 percent of normal.